Energy Saving Sequence 2

[techzone12]

I have a large commerical office building with a fully auomated systems. The HVAC (BAS) system is controlled by DCS controllers. It has multiple AHU units, VAV units, Chillers, etc.

I am trying to come up with sequences to save energy. We are already using economizer mode (free fresh air), when the weather is permitting(based on enthalpy).

We are considering another addition to the sequence (for extra savings), and it goes as follows:
If the OA Temp is too low (< 40) then don't allow the VAV space setpoint to go above 72 degrees. If the OA temp is too high (> 70) then don't allow the space setpoints to go below 72 degrees. Of course we can use enthalpy instead of just temperature.

Any suggestions?

 

[lcleveland]

some things come to mind, reset the ahu supply air temp occording to vav demand, reset the ahu supply static pressure based on vav damper position and demand, do an internet search on ahu sequences, many big projects post the sequences.

 

[techzone12]

Thanks for the feedback. Another idea that came to mind, is to reset VAV temp setpoints when the KW peak is approached. Since peak KW will cost much more $$.

 

[stanlsimon]

Most people can live with 78 space temp in summer. 80 is even better. California title 24 used to prescribe 80. There will always be complainers, but they can be minimized if you keep some air moving on occupants.